“Microbiome” research has, in recent years, been principally defined as the analysis of the genetic potential inherent to microbial communities, via high throughput DNA/RNA sequencing and computational analyses. These types of studies have produced an added dimension and granularity to our recognition of the recruitment and contributions of microbes as an extension of ourselves that affect our health and well-being; including our resistance or susceptibility to relapse of chronic diseases such as obesity and metabolic diseases. Many clinical and small animal studies have now established that variations in the microbiome are associated with obesity and related conditions, and microbiota transplants in small animal models have provided further evidence to suggest that adiposity and weight gain can be transferred to naïve hosts, further establishing the links between the microbiome and obesity. Now, “microbiome” research is expanding beyond its recent foundations in genomic sciences and returning to its original definition: to understand the interactions and processes inherent to a microbial community (micro-), placed in context with the physiochemical attributes of their surrounding environment (-biome). This presentation will address some of the basic concepts inherent to emergence and evolution of microbiome research, with specific reference to some key advances in understanding the interactions between the host and the gut microbiome in obesity. The presentation will also emphasize two concepts: how metagenomic approaches applied to the microbial world has provided new insights into the role of the microbiome in obesity and related conditions; and how the translation of microbiomes to medicine will be augmented by the application of these principles, along with “classical” microbiology techniques.